This invention relates to agricultural balers and more specifically to balers of the traditional rectangular type, i.e., balers which produce bales of crop material which are rectangular in side view.
In U.S. Pat. No. 4,525,991 there is disclosed a baler of basically conventional design in that it comprises a bale case or chamber in which a bale of crop material is formed, having an inlet opening communicating with a feeder duct in which charges of crop material are accumulated which subsequently are transferred or stuffed in the bale case for compression by a reciprocable plunger operating within the bale case. In this particular baler, the packing of crop matreial into the feeder duct to form a charge is effected by packer tines extending along a tine bar rotatable within the feeder duct, and the stuffing of an accumulated charge into the bale case is accomplished by stuffer tines mounted on the tine bar and offset from the packer times such that the outer ends of the respective sets of tines follow different paths which are preferably generally apple-shaped.
This feeding and stuffing arrangement has been found generally satisfactory except that with certain crops and crop conditions the feeding operation is less than satisfactory whereby the overall baler capacity is reduced accordingly and the top filling of the bale case is sometimes insufficient so that bales of irregular density are produced. The reason for this is that, if silage or a very wet crop, for example, is being handled, it is to some extent compressed by the packer tines as it is fed thereby into the feeder duct and a given charge tends not to recover from the compression in contrast to dry hay or straw, for example, which springs back on being released after compression and this nature resilience means that the hay or straw engages the adjacent walls of the feeder duct and thus maintains its position in the duct. However, with silage and other crops which does not have this natural resilience, there is a tendency for a given charge to fall under gravity once presented to the feeder duct by the packer tines. The greater the time lag between successive packer tine entering the feeder duct, the further a charge is likely to fall.
This problem is aggravated in larger balers which are becoming increasingly popular